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You wouldn't need to move all of the breakers on one side down. Just move the two top circuits where the generator breaker will go down to the bottom. The two hot wires being moved need to be extended inside the panel using standard twist-on wire connectors and some matching gauge black or red wire.
Agreed, this keeps the panel circuit labels mostly untouched.

i would do a couple of tandems then also add an whole house surge protector as well
and also look at a meters box as an add on.
pm if you need links.
Good suggestion but The panel isn’t listed for tandems. Unless square d‘s homeline breakers has a non circuit limiting tandem like QO Does.
 

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This site has alot of good info on pipe sizing.

My suggestion is to draw a pipe map with lengths and diameters For us to see And for your own experience. Your system looks to be 3/4 and 1/2 in those pictures. I can almost guarantee that you don’t have enough volume tapping into your existing system. A home run from the meter would be the best move.

Your generators 439cc engine is approximately 14-15hp. A safe rule of thumb is 10,000btu per HP, so 150,000 btu of supply volume will guarantee proper fuel Quantity. In all likely hood you’ll need far less supply during normal operation with the generator mildly loaded but that leaves zero reserve for when other NG appliances are operating. Inadequate supply can cause the generator to bog and send voltages and frequency tumbling. It’s not worth damaging your devices and appliances.
 

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Well I had alot of fun after Thanksgiving dinner lol! Thank you so much for the information and the link to the generator pipe size page. Incredibly helpful! Attached is the pipe layout for my house as well as the calculations I came up with. I am pretty sure I have 1" and 1/2" pipes. I measured the circumference of each and used a pipe size chart I found and it looks like those are the pipe sizes. I don't believe I have any 3/4" pipes. In addition to the 2 notes in the diagram, there were several BTU numbers on my gas boiler so I included 2 of them. Note that the boiler is 30 years old. Here are some comments on my calculations. I realize this is new to me and I may be way off on my assumptions:
  • I used the 14.5 horsepower number you provided and the 145 CFH full load number that was derived from the horsepower. One thing I wondered about was that the generator specs have the generator running natural gas at 69% of the wattage compared to gasoline. I was wondering why that is and whether the CFH full load number with natural gas is also 69% which would be around 100 CFH.
  • The only thing off of legs I, J, K and L is the gas grill. If it is not used during an outage, that seems to give me 73 CFH which seems to get me close to the 100 CFH number but pretty far away from 145 CFH.
  • If I was to tap off of Leg G, that should give me 180 CFH (286 - 106) which would get me to both numbers but where does that leave the gas stove when that needs to be used? The 55,000 BTUs is if all 4 burners + oven are used at 100%, but at 2 burners + oven that would be fine if we are trying to get through a power outage. Seems like that would fit within the available CFH.
It seems like tapping off of Leg G (before the gas stove) is the way to go. It's certainly doable because it should be fairly easy to tap in there and run a line to the outside wall. It would be close to where I was planning on locating the generator as well. Of course, that would require a plumber and extra expense. I'd love to be able to run it off of the existing 1/2" line but that may not work if 73 CFH is not enough. Let me know your thoughts on all this. If anyone else wants to chime in, please do.

Finally, what did you mean in your last post by "A home run from the meter would be the best move. ". Thanks again!
Nicely done. The pipe map really clears things up. I agree tapping off of G should be satisfactory. The 1” x 1/2” x1” tee can be replaced with a 1”x1”x1” and keep 1” all the way to the end necking down to the right sized quick disconnect.

The only limiting factor to your system is the gas meter itself. Most are rated for 250cfh. A buddy of mine that works for the gas company tells me that there is more wiggle room to that number as long as the distribution lines in the street are under pressure. Essentially if you have a pressure regulator before your meter.

“home run” meaning a dedicated pipe from at the meter to the generators location. Since your trunk line is 1” you should be ok. If the trunk line was 3/4 tapping off of it would not have been sufficient.
 

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1/2 pipe has a steep drop off as it get longer. A few feet is one thing but a total of ~30ft including restrictions from elbows and quick connects cannot support enough gas volume.

just remember the gas pipe size is the inside diameter.
This is a good point, 3/4” black pipe has a ~1” outer diameter. Make sure you have your measurements correct.

Nominal size [inches]Outside diameter [inches]Outside diameter [mm]Wall thickness [inches]Wall thickness [mm]Weight [lb/ft]Weight [kg/m]
1/8 inches0.405 inches10.3 MM0.068 inches1.73 MM0.24 lb/ft0.37 kg/m
1/4 inches0.540 inches13.7 MM0.088 inches2.24 MM0.42 lb/ft0.84 kg/m
1/2 inches0.840 inches21.3 MM0.109 inches2.77 MM0.85 lb/ft1.27 kg/m
3/4 inches1.050 inches26.7 MM0.113 inches2.87 MM1.13 lb/ft1.69 kg/m
1 inches1.315 inches33.4 MM0.133 inches3.38 MM1.68 lb/ft2.50 kg/m
1 1/4 inches1.660
 
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